Answer:
Following are the program in c++ language
#include <iostream> // header file
using namespace std;// namespace
int main() // main function
{
int num; // variable declaration
long int f=1; // variable declaration
do
{
cout<<"Enter the Positive value:";
cin>>num;
} while(num<0); // i check whether number is non negative or not
while(num>0) // iterating over the loop
{
f=f*num; // calculate the factorial
num--; // decrement the value of num by 1
}
cout<<" factorial is :"<<f; // display the factorial .
return 0;
}
Output:
Enter the Positive value:7
factorial is :5040
Explanation:
Following are the description of the program .
- Read the input by user in the "num" variable of "int" type..
- The do-while will check the enter number is nonnegative number.
- While(n>0) loop is calculating the factorial in the "f" variable .
- Finally display the factorial .
